Issues with Labeling

[JoanieSmitheroni]

Our son is 2 1/2 and for the most part seems to have a fairly large vocubulary and speaks very clearly.  However, he seems to have issues labeling words correctly.  As an example, he will point to a football helmet and say, "look, a soccer ball" or if we are eating pizza, he will say, "more chicken please."  

He has only recently started calling me, "Mommy" and my husband, "Daddy."  Before that he would call either of us either name or sometimes just call us, "mommydaddy."  He calls squirrels, "lions" and all juice, "lemonaid."

We've had plenty of folks (teachers, pediatrician) tell us that he is "only 2" but the consistency with which is mis-labels words and the way that he does so by category is pretty noticeable.  He puts together fairly complex sentences so the issue is specific to labeling words.  

His preschool class has been focusing on colors this week and while we are not surprised that he will just all everything, "green," it does make me worry he will struggle with reading and the ability to name letters.  Is there any particular language disorder that relates to labeling?  While we would be interested in pursuing help, it seems like it will be tough to get anyone on board when he is really talking quite well and unless you spend quite a bit of time with him, you may not pick up on the issue.

Thanks,
Joanie